Sewage disposal apparatus



Filed Feb. 15, 1953 4 Sheets-Sheet 1 NWO June 9, 1936. c. N. WINDECKER SEWAGE DISPOSAL APPARATUS Filed Feb. 15, 1953 4 Sheets-Sheet 2 game/rm C (AMA/ u.

Mm fl /muh June 9, 1936. c. N. WINDECKER SEWAGE DISPOSAL APPARATUS Filed Feb. 15, 1935 4 Sheets-Sheet 3 June 9, 1936. c. N. WINDECKER SEWAGE DISPOSAL APPARATUS I Filed Feb. 15, 1933 4 Sheets-Sheet 4 Patented June 9,

UNITED STATE 8 Claims.

4 This invention relates to a process and apparatus for use in sewage disposal and concerns primarily the drying and burning or other dispositionof wet sludge resulting fromtreatment of 5 various kinds.

It is well known that the sludge which is formed as an end product in various treatments of sewage contains a considerable percentage of organic matter and therefore cannot be dumped as it could if it contained only inorganic matter. This fact leads to the necessity for incineration or some other suitable disposal of the sludge. This invention relates to disposal by incineration and has for its object to provide for such incineration at minimum expense and by use of the simplest mechanism possible consistent with good results.

In order that the organic matter may be removed from the sludge by burningpit is necessary that the sludge should be first dried in order that it may be burnt quickly to avoid slow combustion and the production of noxious odors. I have found that where an attempt is made to incinerate this material by passing it slowly along an,

inclined tube at one end" of which combustion is occurring, the material must traverse all temperature ranges from a relatively low temperature at one end of the tube to the temperature of combustion at the other. In such a process there exists a temperature range which in this specification I term the "scorching range wherein the I complex organic compounds existing in this material are only partially broken down and give rise to various complex and malodorous fixed gases. This scorching rangemay vary from 212 F. to the neighborhood of 1400 F. according to the composition of the sludge.

Broadly stated, it is the object of my invention to dry the sludge to a small moisture content at temperatures elevated considerably above or- 4 dinary room temperatures but below the scorching" range and then introduce the dried sludge into a combustion chamber where the temperature is maintained above the scorching range, that is, at a temperature at which the malodorous gases are not stable. The combustion chamber should be above 1200 F. and may preferably be about 2000 F. Depending upon thepercentage of organic matter contained in the sludge, it may be necessary to add a greater or lesser amount of combustible material in order to maintain the combustion temperature at. the desired point. For this purpose, I prefer to grind the sludse and introduce it with the additional combustible to promote the quickest and most complete combustion.

Referring now tov the accompanying drawings wherein Figs. 1 and 1! constitutes. schematic. vertical sectional elevation of an apparatus for carrying out my improved process; Fig. 2 is a view on line 2-2 of Fig. 1; Fig. 3 is a view on line 3-4 of Fig. 1; Figs. 4 and 4- constitute a schematic vertical sectional elevation of a modified form of s ms r ornc i apparatus; Fig. 5 is a section on the line 5-4 of Fig. 4; Fig. 6 is a section on the line C-J of Fig. 4' and Fig. 'l is a fragmentary sectional view corresponding, to-a portion of Fig. e1 with the manifold ii and pipes 82 omitted. I shall describe two 11- lustrative mechanisms for carrying out my improved process, the first to be described being applicable to those sludges which do not give up objectionable odors to gases passed in actual contact therewith at working temperatures and the second of somewhat more complicated construction being adaptable for other sludges.

Referring now to the apparatus of Figs. 1 to 3 inclusive, the numeral l0 indicates generally a cylinder within which the drying and burning is carried out and which may be conveniently considered as divided into a drying portion ll provided on the interior face with agitating Z-bars l2. a refractory lined cylindrical portion I3 defining a combustion chamber and a battle section II between the end of the cylinder l3 'and the agitating bars II. The portion I! may consist of a metallic shell l5 lined with fire brick I 6 and telescoping a portion of the shell II. M. The cylindricalmember I3 is spaced fromsaid shell by spiders ,l'l which permit the passage of air. I have shown the memberli as rotatable with the remainder of the cylinder l0, although it is to be understood that provision maybe made for independent rotation of these two or for the combustion member I31 remaining fixed, although preferably the construction is as shown, since the downward slope provides for feeding of 110119 combustible material towardthe lower end and into the outlet member i8 from which it drops through an opening is upon a conveyor 20 by means of which it is carried away for any preferred disposition. Wherever the word cylinder" is used herein, it is to be understood as indicating the entire tube It, including the member I3, unless the context otherwise indicates, but not in a limiting sense.

The drying portion of the tube is provided at the upper end with angularly extending members -2l defining a helicalfeed adapted to transfer wet sludge toward the z -bars i2. This feeding operation is relatively rapid as compared to the progress of the sludge from one end ofthe z-bars to in embracing relation to the spouts for causing all the discharged material to be deposited upon 'such' conveyor. 24 feeds out dried sludge without admitting airto pass through spouts 22.

It is to be understood that the portion I l of the tube IOfmay be constructed of material of low heat conductivity or it may be insulated either interiorly or exteriorly, preferably the latter.

The bailie portion l4 of the tube I is provided with a series of battles 25 which may be of any shape as, for example, that shown, a plurality of plates of slightly more than semi-circular obstructing value as will be clear from Figs. 1 and 3. These baflles prevent the passage of high temperature gas currents within the tube and cause uniform mixing of the gases so that the material in the drying portion II will be subjected to incoming gas of substantially uniform temperature. Such temperature can be regulated by the length of the cylindrical portion l3 and by the amount of air passing between the member l3 and the outer shell. The baiiles also serve to mix the air from this source with the gases and heated gases from the-combustion chamber. It is to be understood that thermostatic means may be provided within or adjacent to the cylindrical portion I4 for controlling the amount of air admitted be tween the member l3 and the outer shell either by a valve controlling such supply or by regulation of the speed of the motor 26 as will hereinafter more clearly appear. It will be understood that the Z-bars l2 operate to agitate the sludge, prevent the formation of large lumps and thereby give better access of the heater gases to this material. Other agitating means maybe substituted or added as will be obvious to one skilled in the art. The cylinder in may be rotatably supported by a plurality of rollers 21 suitably supported on foundations 28, 29 and 30; Mounted upon the block 30 is a motor 32 connected through a suitable reducing gear mechanism 33 in driving relation to a pinion 34 meshing with a ring gear 35 surrounding the cylinder l0.

The wet sludge is fed to a hopper 36 by means of a conveyor 31, from which it is fed into the upper end of the cylinder II) by a feed screw 33 rotated in a suitable housing 39 by a motor 40. The upper end of the cylinder I0 is closed by a seal 4| working within a cylindrical flange 42 of a housing means 43 in alignment with the stack 44. A passage 45 leads from the housing 43 to the stack 44 below a damper 45 to a dust collector 41 which may be of the battle type, as shown, or a screen type, and thence through a condenser or scrubber 48, through a fan 49,

driven by the motor 26, and back through a pipe 50 to the stack 44 above the damper 46. The passage 45 is provided with a damper 45 which may be closed when the device is started to render effective the stack draft, or for controlling the draft through the cylinder in. While the dust collector 41 is provided for the purpose of removing any dust that may reach that point, the amount will be small since the wet sludge in the cylinder I 0 is being agitated and will hold any dust which may contact it, and since the cylinder in the drying portion will normally be heavily charged with water vapor, the wet sludge fed thereinto normally containing above 50% by weight of water. Within the condenser or scrubber 48 is a manifold from which perforated spray heads 52 are taken off for spraying into this chamber cold water supplied through a pipe 53. This mechanism will remove most of the water vapor and prevent the emission from the smoke stack 44 of clouds thereof, as would otherwise cur. As hereinbefore indicated, the draft through the cylinder l0 may be regulated either thermostatically or manuallyby the speed of the motor 26. It may also be regulated by the damper 45 within the passage 45. Should a dust collector and condenser be found unnecessary they may be omitted, and the gases discharged directly into the chimney where any residual odor occurring can be destroyed by the addition of a very small amount of chlorine gas, or chlorides.

The conveyor 23 delivers the dried sludge into a compartment 54 of a hopper 55. A conveyor 56 delivers coal or other fuel into a compartment 51 thereof and the two compartments are in adjustable communication with each other and deliver to a passage 58. The movable baiiie 59 may be used for the purpose of varying the proportion of material delivered from the two compartments. The dried' sludge and fuel in proper proportions are delivered to a combined mill and fan 50 wherein the materials are beaten or otherwise milled into a state of fine subdivision and blown by the fan operated by the motor 6| .through a feed-in tube 62 to the combustion chamber, that is, to the interior of the member l3.

From the foregoing, it will be seen that in operation wet sludge is fed into the upper end of the hydro cylinder l0, progresses during a suitable drying period along the Z-bar agitators, being tumbled the while, after which it is discharged upon the conveyor 23, having been exposed to heated air and other gases at a temperature below the .scorching range. The dried sludge is then carried by the conveyor 23 to the hopper 55 where it is mixed with powdered coal or other suitable fuel and milled to a state of fine subdivision. It is then blown into the combustion chamber where the organic constituents are burned instantaneously above the "scorching temperature range and the gas is passed to the drying chamber while the non-combustible portions work backwardly and are delivered upon the conveyor 20. 5

Referring now to the modified form illustrated in Figs. 4 to 6 inclusive, wherein those parts which correspond to similar parts in the first form have been given the same numerals, it will be seen that I have provided a cylinder Ill and divided in the same general manner into a drying portion I l, a combustion chamber portion I3 over which a portion of the main shell telescopes as indicated at l4 and a baffle section 14. The combustion chamber is defined by a metallic shell l5 lined with flrebrick or other suitable refractory l6and spaced from the main shell by spiders ll of open work formation whereby to permit passage of air therethrough. The termination of the combustion chamber at the inlet end is defined by a member I8 delivering through the opening l9 onto the conveyor 20 in the same manner as in the first described form.

Within the main shell in the drying portion II is telescoped an inner shell I0 spaced from the main or outer shell by any suitable means and provided on the interior with agitating Z-bars l2. The member I0 is provided with a substantially closed end portion ii provided with spouts 13 extending through the mainouter shell and adapted to deliver into the-member 2i and upon the conveyor 23. An opening 13 is provided in said substantially closed end H for receiving a manifold 8| provided with pipes 82 extending adjacent themain shell to a pointnear the end of the member. i3 whereby to admit fresh heated air to the interior of the cylindrical member vIll that the shell 10 is constructed of metal or other material which is a good conductor of heat. Gases passing around the shell 10 are delivered into a pipe M and thence to a stack 15. The air or-gases passing through the opening 13 into the shell 10, together with water vapor and other volatile material arising from sludge introduced thereinto is delivered from the end of the shell Ill at the right hand side on the drawings into a space It from which it passes through a pipe 11 to a device it which may embody a condenser or dust collector or both after which it passes through a pipe 19 to the inlet sideof a fan 80.

which delivers it through a pipe 83 and sleeve 84 surrounding the tube 62 to the interior of the member It, that is, into the combustion chamber.

It will thus be seen that the major portion of the gases from the combustion chamber with a heat tempering admixture of air from the outside passes through the baflie portion Id of the cylinder 10 where it is mixed and that the major portion passes around the shell Ill in heating relation to sludge therein and thence to the stack 15 while the minor .portion passes through the opening or openings 13 to the interior of the shell 10 and carries away water vapor and other volatile material to the device 18 wherein a portion is liquefied and from which the remainder is returned in substantially dry condition to the combustion chamber. By this means the gases discharged from the stack 15 are rendered free of objectionable odors.

The sludge feeding means both for wet and dried sludge, the fuel feed means and the means for rotating the cylinder are the same in this form as that already described and need not be further elaborated. I

From the foregoing, it will be seen that I have provided a method of sewage disposal which possesses the several advantages enumerated and that I have described illustrative examples of apparatus forcarrying the method into efiect. While I have described such illustrative embodiments of my invention, I wish it understood that I am not limited to the details of the disclosure but only in accordance with the appended claims and the prior art.

Having thus described my invention, what I claim is:

1. An incinerator comprising, in combination, a cylinder, means for rotating the same, means for feeding wet sludge into said cylinder, outlet means for removal of dried sludge therefrom, means for mixing such dried sludge with fuel, a combustion chamber, means for feeding the mixture of dried sludge and fuel to said combustion aoasnsa s a chamber; and means for mixing heated gases from said combustion chamber with air and pass ing the gaseous mixture through said cylinder,

said cylinder being formed with passage means for conducting a major portion of saidgaseous mixture in heating relation to wet sludge therein but out of actual contact therewith.

2. In an incinerator, an elongated cylinder,

, combustion end and said baille means.

3. In an incinerator, an elongated cylinder having one end portion insulated to form a combusticn chamber, means for rotating said cylinder, means for feeding wet sludge into the end thereof opposite said combustion chamber, means lfor introducing combustible material to said combustion chamber, outlet means intermediate the ends of said cylinder for removal of dried sludge. and baflle means between said outlet means and said combustion chamber.

4. In a device of the class described, a cylinder comprising a main shell and a cylindrical combustion chamber element telescoping within said A shell, spaced therefrom for admission of air therebetween and terminating in an open end intermediate the ends of said main shell, a second shell within said main shell and spaced therefrom for passage of hot gases therebetween, said second shell having a partially closed end terminating within said main shell in spaced relation to the open end of saidcombustion chamber element, said partially closed end beingprovided with an inlet opening for a small portion of heated air, means for conducting heated air from the space between said combustion chamber element and said shell to said inlet opening, means for drawing gases from the interior of said second shell and'delivering them to the combustion chamber, means for introducing wet sludge to said second shell, outlet means adjacent said partially closed end for removal of dried sludge therefrom, means for pulverizing said dried sludge, and means for introducing said pulverized sludge and fuel to said combustion chamber.

5. In a device of the class described, a cylinder comprising a main shell and a cylindrical combustion chamber element telescoping within said shell, spaced therefrom for admission of air therebetween and terminating "in an open end intermediate the ends of said m'ain shell, 9. second shell within said main shell and spaced therefrom for passage of hot gases therebetween, said second shell having a partially closed end terminating within said main shell in spaced relation to the open end of said combustion chamber element, said partially closed end being provided with an inlet opening for a small portion of heated air, means for conducting heated air from the space between said combustion chamber element and said shell to said inlet opening, means for drawing gases from the interior of said second shell and delivering them to the combustion chamber, means for introducing wet sludge to said second shell, outlet means adjacent said partially closed end for removal of dried sludge therefrom, means for pulverizing said dried sludge, and means for introducing said pulverized sludge and powdered, carbonaceous, solid fuel said combustion chamber.

6. In a device of the class described, a cylinder comprising a main shell and a cylindrical combustion chamber element telescoping within said shell. spaced therefrom for admission oi air therebetween and terminating in an open end intermediate the ends of said main shell, a second shell within said main shell and spaced therefrom for passage oi hot gases therebetween. baille means within said main shell between said combustion chamber and said second shell, said second shell having a partially closed end terminating within said main shell in spaced relation to the open end of said combustion chamber element, said partially closed end being provided with an inlet opening 101' a small portion of heated air, means for conducting heated air from the space between said combustion chamber element and said shell to said inlet opening. means for drawing gases from the interior of said second shell and delivering them to the combustion chamber. means for introducing wet sludge to said second shell, outlet means adlacent said partially closed end for removal oi! dried sludge therefrom, means for pulverizing said dried 10 sludge-and means for introducing said pulverized sludge and fuel to said combustion chamber.

CLIFTON N. WINDECKER. 

